Over medium-high heat, heat the butter in the pressure cooker until it begins to foam. Cook the leeks , stirring frequently, until they soften, about 5 minutes. (If using onions, for a sweeter taste, cook them, covered, over low heat for an additional 5 minutes, stirring from time to time.) Add the water and bring to a boil as you prepare and add the chicken parts, celery, carrots, barley , bay leaves, thyme , and salt.

Lock the lid in place. Over high heat, bring to high pressure. Lower the heat to maintain high pressure and cook for 12 minutes. Quick-release the pressure by setting the cooker under cold, running water. Remove the lid, tilting it away from you to allow any excess steam to escape.

With a slotted spoon, transfer the chicken parts to a cutting board. Taste the barley, and if it is still hard (it should be chewy but tender), return to high pressure for 3 minutes more.

Spoon off any fat visible on the surface. Remove the bay leaves and discard. Stir in the chicken broth and salt to taste and bring to a boil. Add the spinach and boil the soup over medium heat until the spinach is tender, about 2 minutes for fresh and 5 minutes for frozen.

When the chicken is cool enough to handle, remove the meat from the bone and chop or shred it into bite-sized pieces. Return to the cooker. When the chicken is good and hot, turn off the heat and stir in the dill , lemon juice, and salt to taste.

Yield: 6 to 8 servings Variation Thai-Inspired Chicken Soup:

Substitute one 14-ounce can unsweetened coconut milk for 2 cups of the water. Omit the thyme and cook the soup with the finely chopped bulbs of 2 stalks fresh lemongrass. You may add 4 to 6 ounces small, shelled shrimp at the end and boil over medium heat until they turn pink, 1 to 2 minutes. Substitute cilantro or basil for the dill and use lime juice instead of lemon. Season with Japanese soy sauce (tamari or shoyu) instead of salt.

Note: If you cannot find fresh lemongrass, look for Thai Kitchen's lemongrass bottled in a light brine. Do not use dried lemongrass.